The Obama administration last week gave eight states and the District of Columbia con­ditional approval to operate health insurance exchanges, the online marketplaces where consumers will use federal subsidies to purchase insurance policies. The designation recognizes that these states have made enough progress to hit a crucial deadline: launching for open enrollment on Oct. 1, 2013. The exchanges will also need to begin collecting subsidies in January 2014. Most states have opted not to take full control of their insurance exchanges. The consulting firm Avalere Health estimates that 32 states will leave it to the federal government to run their marketplaces or work in partnership, taking on select responsibilities.